Many good points about the possibility of the door panel of another Mustang not matching; paint does vary from batch to batch. However, I believe that the Mustang black isn't a metallic, so I wouldn't be so much worried about a perfect shade match as I would about an "orange peel" match. Nevertheless, I'd take a new, unblemished, door any day verses one the was straightened with bondo filler. Just my two cents.
2014 Mustang GT Coupe Premium. Options include: California Special package, comfort package, navigation, glass roof, shaker pro system, 3.73 ratio limited slip axle, GT front grill/fogs, MGW race spec shifter, BBK X-Pipe, Corsa GT500 Quad Sport axle-back, Ford Racing ProCal tune. "If I wanted insane HP, I would have purchased a 2014 Shelby GT500!"